Estuary

Partially enclosed coastal body of brackish water

An estuary is a partially enclosed coastal body of brackish water where freshwater from rivers or streams meets and mixes with saltwater from the open sea. Estuaries form transition zones between riverine and marine environments and are classified as ecotones, areas where different ecosystems overlap. They are influenced by both marine processes (such as tides, waves, and saline water intrusion) and fluvial processes (including freshwater flow and sediment input).

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